AfternoonI am getting ready for a trip with my Skoolie in 2 weeks and have alot of mnt drivning to doGoing up into Boone NC on hy421 there are several very steep sections 12-19% for short distances.During the summer I had a few issues with temps (engine/tranny not dangerous but still an issue)

After reading and searching I believe I have been driving this combo wrong from the gitgo.

FE 5.9 Turbo with A545 tranny (no lockup)

I keep coming across this type of statement:

Max line pressure 2400 RPM plus

Acceptable full-load engine governed speed

2400-4000 rpm (diesel) 3200-4000 rpm (gasoline)

Minimum engine idle speed (with transmission in drive) 500 rpm

I have been keeping RPMS low about 1800/2000 cruising,when approaching a hill apply alittle more throttle and not much happens and temps start to move up, so I back off and just slowdown.

SO my plans have changed and am thinking to use lower gears(manually down shift, tranny doesnt downshift very well on it's own)

say 2nd gear and keep RPM's up about 2500 rpm's

Is the proper way to drive this?

Sorry for long winded post

Any advice would be good (except get a different bus baby steps right now)

You definitely want to shift down on those grade. As it is, you are letting the torque converter do the gear reduction and making a lot of heat. You want to drive it up a grade so that you still have plenty of throttle under your foot. 2500-2700 sounds about right.

Typical stall rpm on the AT545 is around 1600rpm (you can test this by putting it in drive and with the brakes applied push the accelerator down all the way and see where the rpm stops, then immediately release and let the engine run for another 5 minutes to cool it down). With a non locking torque converter, the higher rpm you run it, the more close to locking up it gets since the pressure builds with RPM. I would run it as close to governor on long hills with your pedal about half up. This should keep the heat down.

Too bad you can't find a 2000 series to put in. They have up to 6spds with 5th and 6th over drives and with a lockup clutch activating on the upper side of 2nd continuous up to 6th. If you're going to keep your bus for a few years-it is worth considering. Good Luck, TomC

Gus-if you have a R-N-D-2-1 shifter on the V730, when you pull it into 1st, the torque converter should lock up both on no accelerator pedal and with half pedal. If you floor it, at any speed in 1st the torque converter will come out of lockup. Good Luck, TomC

Thanks for all the replys.I spoke with several drivers and mechanics.They said depending on final drive ratio.(The one particular hill in question)"By the gas station be slow enough so your in 2nd gear at 2000 rpms and "roll" into the throttle as hill starts you should mantain 2400/2500 rpm with about 3/4 pedal.Don't be afraid to run all the heaters either"

He also said some of the buses could use same technique but would be in 3rd gear.Experiment so your running about 25 mph

This should keep it cool.

I was"babying" it too much using the torque of the engine and not building up the input rpms into the tranny for high line pressure....we shall see

I do this based on your helpful posts many months ago but I can never feel it lock in first. It will do none of the stuff you posted then.

However, I select first with my electric toggle and then when I slow to anything around 30 it will shift down when I push and decrease the throttle. It will then run up to around 34-36mph all day up long grades without overheating. Whether I floor it or use less seems to make no difference but I normally don't use full throttle.

Since I've finally found how to stop overheating in mts I'm happy, took me a long time and your earlier posts helped.

I was going to edit my 1st post so folks wouldn't have to scroll....no edit button??Edit...I see Modify button on this post so must be a time/reply thing

Anyways....Here is my update to the question I asked.

Maybe this will help someone.

My views and thoughts on driving in the mountains with a FE bus with the 5.9 Allison 545 combo.

I just returned from a 400 mile trip from Mnt City TN south thru Boone via 421 past Winston-Salem, I learned a lot and would like to pass it on for others,since I couldn't find the answers I needed.

Disclaimer:these are my two penny"s and use them as you like.

I was having over heating issues (due to tranny temps climbing as well as coolant temps climbing) not dangerously high yet but high enough I had to stop and sometimes not continue up smaller mountain's since I have had the bus for the last 6months.

the answers to POINT ONE (1 penny).............................

I asked a few older school bus drivers"how do you drive up this mt, w/o over heating or killing the trans?"

they said (I shorten the stories but this is basic info)"2200 rpm is the magic number,find your speed in each gear at 2200 on flat ground and make that the minimum plus 5 mph for each gear"

I approached the mountain and slowed to about 25mph, shifted down to 2nd and rolled into throttle building boost and held it at 2200/2300 rpm when I hit the rpm i was doing 30 mph and several miles later I was in Boone,N.C. coolant/trans never went above 185 engine and 200 trans (convertor out)

Perfect!!

We continued on following same guidelines I established:

1st gear=15-20mph 2200 rpm2nd gear=30-35mph 2200 rpm3rd gear=45-50mph 2200 rpm4th gear was useless to me since the rolling hills never let me use it with out being below my target rpm, and tranny would slip as boost built and temps would rise,so I drove a gear down,and 50mph.

POINT NUMBER TWO (2nd penny)

Heading out of Boone down 421 was the mountain; an evil 6 miles down into N.Wilkesborro

I put tranny into 1st at top of hill and crested at about 10 mph (no lockup convertor)rpm's made tranny shift into 2nd,since I was playing the game of precaution I was nervous and used 30mph as my "set speed" I had to apply the brakes several times and even pulled over and checked brake temps ata spot between the runaway ramps...cool to touch OK I'm good so we continued on.so I basically coasted hoping the tranny and engine would hold us back

Here is the point :wink:

on way back,I climbed the mt with no worries and no temp variation...cool...but I had 2 down hills that worried me.I crested and rolled by the Eastern Continental Divide sign and knew there was a red light at the bottom of the grade...

I shifted into 1st gear and drove at about 1500 rpm to make the transition from flat to down hill, as I was "driving" down the mountain contemplating how I would approach this light I realized that I was all ready 1/3 way down and still doing 15 mph!!!! :shock:As long as I "drove" not coasted, the tranny held back just fine....so I drove down that incline in 1st gear at 1500/1700 rpm...I feathered throttle to maintain pressure but not rev motor.

I was happy.

The road out of Boone back towards Mt City is a lot steeper with a damn gas station at the bottom.I "drove" down at 20 mph and 2000rpm,when engine started to creep up I used my left foot to apply the brakes for a split second(2 times total) so I still had throttle pressure applied

Sorry this is so long winded, I hope this helps someone out and gives them an idea or 2...